The Fifth Edition builds on the strengths of prior editions in providing a unique combination of the law and economic theory of patents with extensive and diverse legal analyses and practitioner insights. Updated to address the extensive developments that have arisen over the few years since the Fourth Edition, the Fifth Edition is also shorter in length. A wealth of supplementary materials are provided in the accompanying website, including full versions of background documents such as patent files, unedited versions of important cases, extra reading, and special materials designed to help students during their studies as well as while seeking a job.